Mercurial > sdl-ios-xcode
annotate docs/man3/SDL_SemTryWait.3 @ 4171:3012f1c37361 SDL-1.2
Fixed bug #619
Description From Tim Angus 2008-08-31 03:38:36 (-) [reply]
When pressing "system keys" e.g. ALT+F4 etc., the default for the windib driver
is to ignore them completely, whereas with the directx driver they're handled
(badly as it turns out).
As the windib driver is the default, I assume its behaviour is considered
correct, so the following patch makes the directx driver the same in this
regard.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Mon, 13 Apr 2009 08:44:48 +0000 |
| parents | 4e3b250c950e |
| children | 1238da4a7112 |
| rev | line source |
|---|---|
|
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
1 .TH "SDL_SemTryWait" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" |
| 0 | 2 .SH "NAME" |
|
4107
4e3b250c950e
Erik Heckers fixed bug #493
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
3 SDL_SemTryWait \- Attempt to lock a semaphore but don\&'t suspend the thread\&. |
| 0 | 4 .SH "SYNOPSIS" |
| 5 .PP | |
| 6 \fB#include "SDL\&.h" | |
| 7 #include "SDL_thread\&.h" | |
| 8 .sp | |
| 9 \fBint \fBSDL_SemTryWait\fP\fR(\fBSDL_sem *sem\fR); | |
| 10 .SH "DESCRIPTION" | |
| 11 .PP | |
| 12 \fBSDL_SemTryWait\fP is a non-blocking varient of \fI\fBSDL_SemWait\fP\fR\&. If the value of the semaphore pointed to by \fBsem\fR is positive it will atomically decrement the semaphore value and return 0, otherwise it will return \fBSDL_MUTEX_TIMEOUT\fR instead of suspending the thread\&. | |
| 13 .PP | |
| 14 After \fBSDL_SemTryWait\fP is successful, the semaphore can be released and its count atomically incremented by a successful call to \fISDL_SemPost\fR\&. | |
| 15 .SH "RETURN VALUE" | |
| 16 .PP | |
| 17 Returns \fB0\fR if the semaphore was successfully locked or either \fBSDL_MUTEX_TIMEOUT\fR or \fB-1\fR if the thread would have suspended or there was an error, respectivly\&. | |
| 18 .PP | |
| 19 If the semaphore was not successfully locked, the semaphore will be unchanged\&. | |
| 20 .SH "EXAMPLES" | |
| 21 .PP | |
| 22 .PP | |
| 23 .nf | |
| 24 \f(CWres = SDL_SemTryWait(my_sem); | |
| 25 | |
| 26 if (res == SDL_MUTEX_TIMEOUT) { | |
| 27 return TRY_AGAIN; | |
| 28 } | |
| 29 if (res == -1) { | |
| 30 return WAIT_ERROR; | |
| 31 } | |
| 32 | |
| 33 \&.\&.\&. | |
| 34 | |
| 35 SDL_SemPost(my_sem);\fR | |
| 36 .fi | |
| 37 .PP | |
| 38 .SH "SEE ALSO" | |
| 39 .PP | |
| 40 \fI\fBSDL_CreateSemaphore\fP\fR, \fI\fBSDL_DestroySemaphore\fP\fR, \fI\fBSDL_SemWait\fP\fR, \fI\fBSDL_SemWaitTimeout\fP\fR, \fI\fBSDL_SemPost\fP\fR, \fI\fBSDL_SemValue\fP\fR | |
|
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
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41 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00 |